Severe malabsorption in autoimmune polyendocrinopathy-candidosis-ectodermal dystrophy syndrome successfully treated with immunosuppression

Leber congenital amaurosis as the initial and essential manifestation in a Chinese patient with autoimmune polyglandular syndrome Type 1

PURPOSE

Autoimmune polyglandular syndrome Type 1 (APS-1) is a rare autosomal recessive disorder caused by defects in the autoimmune regulator (AIRE) gene. Patients are generally diagnosed at ages between five and fifteen years when they exhibit three or more manifestations, most typically mucocutaneous candidiasis, autoimmune Addison's disease, and hypoparathyroidism. Our study aims to report the first case of a Chinese APS-1 patient, presented with LCA as the initial and essential clinical feature of this rare syndrome.

METHODS

Detailed medical and family history were recorded for the patient. Also, the comprehensive ophthalmological examinations were conducted. Whole exome sequencing (WES) was applied to screen pathogenic variants. Sanger sequencing validation and segregation analysis were further performed for confirmation.

RESULTS

A 3-year-old boy with severely impaired vision and initially referred as LCA. However, with a detailed history review, oral candidiasis, dental enamel hypoplasia, and nail candida infection were revealed. Moreover, genetic analysis revealed the homozygous c.769C>T (p.R257X) in AIRE gene (NM_000383.3) as the causative variant.

CONCLUSION

We presented one case diagnosed with APS-1 based on clinical characteristics and genetic analysis. Our study demonstrated that LCA could serve as a warning sign for APS-1 and a potential trigger of early screening, which might prevent life-threatening complications.

Anti-CD45RC antibody immunotherapy prevents and treats experimental Autoimmune PolyEndocrinopathy Candidiasis Ectodermal Dystrophy syndrome

Targeted monoclonal antibody (mAb) therapies show great promise for the treatment of transplant rejection and autoimmune diseases by inducing more specific immunomodulatory effects than broadly immunosuppressive drugs routinely used. We recently described the therapeutic advantage of targeting CD45RC, expressed at high levels by conventional T cells (Tconv, CD45RChigh), their precursors and terminally differentiated T (TEMRA) cells, but not by regulatory T cells (Tregs, CD45RClow/-). We demonstrated efficacy of anti-CD45RC mAb treatment in transplantation but its potential has not been examined in autoimmune diseases. APECED is a rare genetic syndrome caused by loss-of-function mutations of the key central tolerance mediator, autoimmune regulator (AIRE) leading to abnormal auto-reactive T cell responses and autoantibodies production. Herein, we showed that, in a rat model of APECED syndrome, anti-CD45RC mAb was effective both as prevention and treatment of autoimmune manifestations and inhibited autoantibody development. Anti-CD45RC mAb intervention depleted CD45RChigh T cells, inhibited CD45RChigh B cells, and restored the Treg/Tconv ratio and the altered Tregs transcriptomic profile. In APECED patients, CD45RC was significantly increased in peripheral blood T cells and lesioned organs from APECED patients were infiltrated by CD45RChigh cells. Our observations highlight the potential role for CD45RChigh cells in the pathogenesis of experimental and human APECED syndrome and the potential of anti-CD45RC antibody treatment.

Attenuation of Autoimmune Phenomena in a Patient with Autoimmune Polyglandular Syndrome Type 1

Autoimmune polyglandular syndrome type 1 (APS1) is a progressive life-threatening illness with no known cure. Current treatments involve replacement of the hormone deficiencies that result from autoimmune destruction of multiple endocrine organs. We report on a girl whose disease was progressing rapidly until she began on immunosuppressive agents. A healthy 6-year-old girl with no remarkable medical history presented with new onset hypocalcemic seizures and primary hypoparathyroidism. Howell-Jolly bodies consistent with autoimmune hyposplenism were also noted. Genetic testing revealed compound heterozygosity for 2 disease-associated variants in the autoimmune regulator (AIRE) gene. She later developed elevated liver enzymes, primary adrenal insufficiency, and alopecia totalis. Serologic testing revealed antibodies to 21-hydroxylase, intrinsic factor, and smooth muscle. Hydrocortisone was initiated for adrenal insufficiency. Shortly afterwards, her liver enzymes normalized, and her smooth muscle antibody levels began to decline. Serologic testing performed at age 11 revealed seropositivity for glutamic acid decarboxylase (GAD) antibodies, antinuclear antibodies, and Sjögren syndrome A (SSA) antibodies. At age 12, she was given 2 doses of rituximab. Hair loss rapidly progressed to alopecia totalis and then to alopecia universalis, at which time oral methotrexate treatment was initiated. For the past 7 years while on glucocorticoid and methotrexate treatment, our patient has displayed normalization of 2 antibodies, a lack of progression to additional autoimmune diseases, and experienced reversal of alopecia universalis.

Case Report: Severe Hypocalcemic Episodes Due to Autoimmune Enteropathy

Autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED) is a rare monogenic disorder, associated with endocrine deficiencies and non-endocrine involvement. Gastrointestinal (GI) manifestations appear in approximately 25% of patients and are the presenting symptom in about 10% of them. Limited awareness among pediatricians of autoimmune enteropathy (AIE) caused by destruction of the gut endocrine cells in APECED patients delays diagnosis and appropriate therapy. We describe an 18-year-old female presenting at the age of 6.10 years with hypoparathyroidism, oral candidiasis and vitiligo. The clinical diagnosis of APECED was confirmed by sequencing the autoimmune regulator-encoding (AIRE) gene. Several characteristics of the disease-Hashimoto's thyroiditis, Addison's disease, diabetes mellitus type 1 and primary ovarian insufficiency-developed over the years. She had recurrent episodes of severe intractable hypocalcemia. Extensive GI investigations for possible malabsorption, including laboratory analyses, imaging and endoscopy with biopsies were unremarkable. Revision of the biopsies and chromogranin A (CgA) immunostaining demonstrated complete loss of enteroendocrine cells in the duodenum and small intestine, confirming the diagnosis of AIE. Management of hypocalcemia was challenging. Only intravenous calcitriol maintained calcium in the normal range. Between hypocalcemic episodes, the proband maintained normal calcium levels, suggesting a fluctuating disease course. Repeated intestinal biopsy revealed positive intestinal CgA immunostaining. The attribution of severe hypocalcemic episodes to AIE emphasizes the need for increased awareness of this unique presentation of APECED. The fluctuating disease course and repeated intestinal biopsy showing positive CgA immunostaining support a reversible effect of GI involvement. CgA immunostaining is indicated in patients with APECED for whom all other investigations have failed to reveal an explanation for the malabsorption.

Autoimmune polyendocrinopathy candidiasis ectodermal dystrophy

Autoimmune polyendocrinopathy candidiasis ectodermal dystrophy (APECED) is an autosomal recessive disease caused by mutations in the autoimmune regulator (AIRE) gene. This review focuses on the clinical and immunological features of APECED, summarizes the current knowledge on the function of AIRE and discusses the importance of autoantibodies in disease diagnosis and prognosis. Additionally, we review the outcome of recent immunomodulatory treatments in APECED patients.

Gastrointestinal immunity against tryptophan hydroxylase-1, aromatic L-amino-acid decarboxylase, AIE-75, villin and Paneth cells in APECED

Gastrointestinal dysfunction is a disabling manifestation of APECED possibly related to an autoimmune intestinal aggression. We evaluated its features in a cohort of 31 Finnish patients. The most frequent manifestations were constipation (48%), diarrhea, dysphagia and retrosternal pain (45%). AADC and TPH-1 autoantibodies were detected in 51% and 45% of the patients, respectively. Forty-three percent displayed a T-cell response to AADC. One third of the patients also had AIE-75 (33%) and villin (29%)-specific autoantibodies while antibodies against brush borders and Paneth cells were detected in 29% and 20%, respectively. Intestinal IL-17 expression was absent/decreased in 77% of the cases. Duodenal CgA and serotonin expression was absent/decreased in 50% and 66% of the patients, respectively. Constipation correlated with lacking serotonin expression and AADC antibodies (p < 0.05).

Clinical, Genetic and Immunological Characteristics of Paediatric Autoimmune Polyglandular Syndrome Type 1 Patients in Slovenia

Introduction

Autoimmune polyglandular syndrome type 1 (APS-1) is an autosomal recessive disorder, caused by mutations in the AIRE gene. The major components of APS-1 are chronic mucocutaneous candidiasis (CMC), hypoparathyroidism (HP) and Addison’s disease (AD). Clinical, genetic and immunological characteristics of Slovenian paediatric APS-1 patients were investigated.

Methods

Existing medical records of 15 APS-1 patients were rewieved, when necessary, additional clinical and laboratory investigations were issued. AIRE gene analysis was performed to identify causative mutations, and autoantibodies against type I interferons were measured by luminescence immunoprecipitation system.

Results

Patients had one to eight different manifestations of the disease. CMC was present in all, HP in 12/15 (80 %) and AD in 8/15 (53 %) patients. Growth retardation, due to hyposomatotropism, growth hormone resistance, autoimmune thyroiditis, corticosteroid treatment, malabsorption or secretory failure of exocrine pancreas, was observed in altogether 7 (46 %) patients. Six different AIRE gene mutations were detected and p.R257X mutation was present in 63.3 % of pathological alleles. Antibodies against type I interferons were detected in all patients.

Conclusion

APS-1 is a rare disorder with a broad spectrum of clinical manifestations, which, if unrecognized or inadequately treated may be fatal. AIRE gene mutational analysis and autoantibodies against type I interferons are important in early identification of the disease. The aetiology of growth retardation was shown to be extremely diverse, frequently caused by less characteristic manifestations. APS-1 may affect patients’ quality of life in numerous ways, and may cause great psychosocial burden leading to depression and suicidal thoughts even in paediatric patients.

Polyglandular autoimmune syndrome type I - a novel AIRE mutation in a North American patient

Autoimmune polyglandular syndrome type 1 (APS-1), also referred to as autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED), is a rare autoimmune disease that results from autosomal recessive mutations of the human autoimmune regulatory (AIRE) gene. We present the case of a 17-year-old North American girl of primarily Norwegian descent with a novel AIRE gene mutation causing APS-1. In addition to the classic triad of chronic candidiasis, hypoparathyoidism and autoimmune adrenocortical insufficiency, she also has vitiligo, intestinal malabsorption, autoimmune hepatitis, autoimmune hypothyroidism, myositis, myalgias, chronic fatigue, and failure to thrive. Genetic testing revealed heterozygosity for c.20_115de196 and c.967_979del13 mutations in the AIRE gene. The AIRE gene c.20_115de196 mutation has not been previously reported.

A child with autoimmune polyendocrinopathy candidiasis and ectodermal dysplasia treated with immunosuppression: a case report

Introduction

Common features of autoimmune polyendocrinopathy-candidiasis-ectodermal dysplasia include candidiasis, hypoparathyroidism and hypoadrenalism. The initial manifestation of autoimmune polyendocrinopathy-candidiasis-ectodermal dysplasia may be autoimmune hepatitis, keratoconjunctivitis, frequent fever with or without a rash, chronic diarrhea, or different combinations of these with or without oral candidiasis.

Case presentation

We discuss a profoundly affected 2.9-year-old Caucasian girl of Western European descent with a dramatic response to immunosuppression (initially azathioprine and oral steroids, and then subsequently mycophenolate mofetil monotherapy). At four years of follow-up, her response to mycophenolate mofetil is excellent.

Conclusion

The clinical features of autoimmune polyendocrinopathy-candidiasis-ectodermal dysplasia may continue for years before some of the more common components appear. In such cases, it may be life-saving to diagnose autoimmune polyendocrinopathy-candidiasis-ectodermal dysplasia and commence therapy with immunosuppressive agents. The response of our patient to immunosuppression with mycophenolate mofetil has been dramatic. It is possible that other patients with this condition might also benefit from immunosuppression.

Gastrointestinal manifestations in APECED syndrome

Autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED) (or autoimmune polyendocrine syndrome type 1) is a rare autosomal recessive disorder caused by mutations in the autoimmune regulator gene. It causes a loss in central immune tolerance, failure to eliminate autoreactive T cells in the thymus, and their escape to the periphery. APECED patients are susceptible to mucocutaneous candidiasis and multiple endocrine and nonendocrine autoimmune diseases. Although it depends on the series, approximately 25% of APECED patients are affected by gastrointestinal (GI) manifestations, mainly autoimmune-related disorders like autoimmune hepatitis, atrophic gastritis with or without pernicious anemia (Biermer disease), intestinal infections, and malabsorption. In contrast to the major organ-specific autoimmune symptoms of APECED, the GI symptoms and their underlying pathogenesis are poorly understood. Yet isolated case reports and small series depict severe intestinal involvement in children, leading to malabsorption, multiple deficiencies, growth impairment, and possible death. Moreover, very few systematic studies of GI function with intestinal biopsies have been performed. GI symptoms may be the first manifestation of APECED, yet they may have various causes; effective treatment will therefore vary. We provide here an updated review of GI manifestations in APECED, including principles of diagnosis and therapy.

Polyglandular autoimmune syndrome type I

Polyglandular Autoimmune Syndrom type 1 (PAS-1) or Autoimmune PolyEndocrinopathy Candidiasis-Ectodermal-Dystrophy (APECED) is a rare recessive autosomal disease related to Autoimmune Regulator (AIRE) gene mutations. AIRE is mainly implicated in central and peripheric immune tolerance. Diagnosis was classically based on presence of at least two out of three "majors" criterions of Whitaker's triad (candidiasis, autoimmune hypoparathyroidism and adrenal insufficiency). Presence of one criterion was sufficient when a sibling was previously diagnosed. However, some atypic or poorly symptomatic variants do not correspond to these criterions. As a matter of fact, digestive (malabsorption, pernicious anemia, hepatitis), cutaneous (alopecia, vitiligo, enamel dysplasia) or ophtalmological (keratitis) components could prevail. In these cases, diagnosis could be made by molecular genetics. Prognosis is influenced by genetic (AIRE mutations, HLA), hormonal and environmental (infections) factors. Potentially letal components (hepatitis and severe malabsorption) could be treated by immunosuppressors. Candidiasis and other infections should be carefully screened and treated before beginning those therapies, in order to avoid severe systemic infections.

APECED: is this a model for failure of T cell and B cell tolerance?

In APECED, the key abnormality is in the T cell defect that may lead to tissue destruction chiefly in endocrine organs. Besides, APECED is characterized by high-titer antibodies against a wide variety of cytokines that could partly be responsible for the clinical symptoms during APECED, mainly chronic mucocutaneous candidiasis, and linked to antibodies against Th17 cells effector molecules, IL-17 and IL-22. On the other hand, the same antibodies, together with antibodies against type I interferons may prevent the patients from other immunological diseases, such as psoriasis and systemic lupus erythematous. The same effector Th17 cells, present in the lymphocytic infiltrate of target organs of APECED, could be responsible for the tissue destruction. Here again, the antibodies against the corresponding effector molecules, anti-IL-17 and anti-IL-22 could be protective. The occurrence of several effector mechanisms (CD4(+) Th17 cell and CD8(+) CTL and the effector cytokines IL-17 and IL-22), and simultaneous existence of regulatory mechanisms (CD4(+) Treg and antibodies neutralizing the effect of the effector cytokines) may explain the polymorphism of APECED. Almost all the patients develop the characteristic manifestations of the complex, but temporal course and severity of the symptoms vary considerably, even among siblings. The autoantibody profile does not correlate with the clinical picture. One could speculate that a secondary homeostatic balance between the harmful effector mechanisms, and the favorable regulatory mechanisms, finally define both the extent and severity of the clinical condition in the AIRE defective individuals. The proposed hypothesis that in APECED, in addition to strong tissue destructive mechanisms, a controlling regulatory mechanism does exist, allow us to conclude that APECED could be treated, and even cured, with immunological manipulation.

The role of AIRE in human autoimmune disease

The autoimmune regulator (AIRE) gene encodes a transcription factor involved in the presentation of tissue-restricted antigens during T-cell development in the thymus. Mutations of this gene lead to type 1 autoimmune polyglandular syndrome (APS-1), also termed autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED) syndrome, which is characterized by the clinical presentation of at least two of a triad of underlying disorders: Addison disease, hypoparathyroidism and chronic mucocutaneous candidiasis. This Review describes the process of positive and negative selection of developing T cells in the thymus and the role of AIRE as a regulator of peripheral antigen presentation. Furthermore, it addresses how mutations of this gene lead to the failure to eliminate autoreactive T cells, which can lead to clinical autoimmune syndromes.

Clinical manifestations and management of patients with autoimmune polyendocrine syndrome type I

Autoimmune polyendocrine syndrome type I (APS-I) is a monogenic model disease of autoimmunity. Its hallmarks are chronic mucocutaneous candidosis, hypoparathyroidism and adrenal insufficiency, but many other autoimmune disease components occur less frequently. The first components usually appear in childhood, but may be delayed to adolescence or early adult life. There is enormous variation in presentation and phenotype, which makes the diagnosis difficult. Antibodies against interferon-omega and -alpha have recently been shown to be sensitive and relatively specific markers for APS-I, and mutational analysis of the autoimmune regulator gene gives the diagnosis in >95% of cases. The treatment and follow-up of patients is demanding and requires the collaboration of specialists of several fields. However, the literature is especially sparse regarding information on treatment and follow-up; hence, we present here a comprehensive overview on clinical characteristics, treatment and follow-up based on personal experience and published studies.

[Apeced syndrome or autoimmune polyendocrine syndrome Type 1]

Apeced syndrome is a rare disease, with autosomal recessive transmission and associated with mutations of the AIRE gene, which is involved in central and peripheral immune tolerance mechanisms. Its diagnosis is classically based on the combination of any two of the following three major criteria: chronic mucocutaneous candidiasis, hypoparathyroidism and autoimmune chronic adrenocortical insufficiency (Addison disease). One single criterion is sufficient to diagnosis a sibling of a patient already diagnosed. Because of its great phenotypic variability, some atypical or oligosymptomatic forms may not be recognized. In the presence of one of the three major criteria, it is thus important to look for other clinical manifestations--digestive, cutaneous (including keratinized appendages) and ophthalmological (until then considered minor). In these atypical forms, the diagnosis depends on molecular genetics. Prognosis is influenced by different factors that may be genetic (AIRE mutations, HLA), hormonal (sex) or environmental (infections). Potentially fatal disease (hepatitis or severe malabsorption) requires immunosuppressant therapy. Before beginning this aggressive treatment, underlying infectious foci, especially of candidiasis, must be sought and treated to prevent the development of extremely serious systemic infections in this context. A workup for splenic atrophy is also recommended.

Pernicious anemia and widespread absence of gastrointestinal endocrine cells in a patient with autoimmune polyglandular syndrome type I and malabsorption

CONTEXT

Autoimmune polyglandular syndrome type I (APS I) is characterized by multiple endocrine gland failures, with other manifestations such as gastrointestinal (GI) symptoms.

OBJECTIVE

The objective of the study was to study the histopathological and immunological findings in the GI mucosa of a patient with typical features of APS I, malabsorption, and pernicious anemia.

DESIGN AND PATIENT

Biopsies from the GI tract of a patient with APS I were immunostained with chromogranin for GI endocrine cells (GIECs). Blinded slides were graded for numbers of endocrine cells. Normal gastric mucosa was exposed to the patient's serum to test for circulating anti-GIEC and antiparietal cell antibodies using indirect immunofluorescence.

SETTING

The study was conducted at the Departments of Pediatrics and Medical Gastroenterology in an academic medical center.

RESULTS

The patient's GI mucosa demonstrated absence of GIECs throughout, including gastric gastrin-secreting cells, and her laboratory tests for serum gastrin levels were low normal. Both GIECs and parietal cells were absent in her gastric corpus. The patient's serum contained anti-GIEC antibody but no antiparietal cell antibody.

CONCLUSIONS

These observations suggest that GIECs in APS I are subject to an autoimmune destruction that can cause widespread GIEC loss. This could explain the GI dysfunctions that are often noted in the syndrome including malabsorption and atrophic gastric changes with pernicious anemia. We also hypothesize that absence of gastric parietal cells may result mainly from hypogastrinemia that is mainly the loss of gastrin-secreting cells rather than from immune-mediated destruction of parietal cells like that seen in the atrophic gastritis associated with adult-onset pernicious anemia.

Immunophenotypic characterisation of peripheral blood lymphocytes in autoimmune polyglandular syndrome type 1: clinical study and review of the literature

Autoimmune endocrinopathies are characterised by an increased number of peripheral blood lymphocytes (PBL) expressing activation/ memory markers on their surface. The aim of this study was to determine whether a similar finding could be detected in a group of 11 paediatric and young adult patients suffering from autoimmune polyglandular syndrome type 1 (APS1), also called autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED), as very few data have previously been reported in this field. The control group was made up of 11 sex- and age-matched healthy subjects. Fifteen lymphocyte subsets were compared, in terms of percentage and absolute number, and statistical analysis was performed by the Mann-Whitney test. Measurement of T (CD3+), B (CD19+), natural killer (NK, CD3-CD16/56+), CD4+ and CD8+ T lymphocytes showed that patients with APS1 had a higher percentage and absolute count of T lymphocytes: this was entirely due to the statistically larger CD3+CD4+ fraction. Patients with APS1 also had slightly fewer B and NK lymphocytes, but the difference was negligible. Comparison of CD4+ subpopulations bearing activation and naive/memory antigens (marked by CD69, CD25, anti-HLA-DR, CD45RA and CD45RO) showed that patients with APS1 had generally larger percentages and absolute counts of these subsets: however, only the percentage and absolute size of the CD4+CD25+ subset (p = 0.0354 and p = 0.0151, respectively), and the absolute number of the CD4+ anti-HLA-DR+ and CD4+ CD45RO+ subsets (p = 0.0193 and p = 0.0209, respectively) were significantly higher. Interestingly, patients with APS1 also had significantly fewer CD8+CD11b+ and CD3-CD8+ cells. In conclusion, PBL distribution in APS1 resembles that of other autoimmune diseases. Further studies are needed to confirm and possibly extend these data.

APS-I/APECED: the clinical disease and therapy

The clinical picture and course of APS-I or APD-I/APECED is widely variable: the list of possible disease components includes some 30 disorders. The initial manifestation may not include any of the known characteristic components, namely, mucocutaneous candidiasis, hypoparathyroidism, or adrenocortical insufficiency. Although mutation detection is available, it does not help to exclude this disease. Diagnostic strategy needs to be based on knowledge of the clinical picture, including the features of ectodermal dystrophy.

Autoimmune adrenal insufficiency and autoimmune polyendocrine syndromes: autoantibodies, autoantigens, and their applicability in diagnosis and disease prediction

Recent progress in the understanding of autoimmune adrenal disease, including a detailed analysis of a group of patients with Addison's disease (AD), has been reviewed. Criteria for defining an autoimmune disease and the main features of autoimmune AD (history, prevalence, etiology, histopathology, clinical and laboratory findings, cell-mediated andhumoral immunity, autoantigens and their autoepitopes, genetics, animal models, associated autoimmune diseases, pathogenesis, natural history, therapy) have been described. Furthermore, the autoimmune polyglandular syndromes (APS) associated with AD (revised classification, animal models, genetics, natural history) have been discussed. Of Italian patients with primary AD (n = 317), 83% had autoimmune AD. At the onset, all patients with autoimmune AD (100%) had detectable adrenal cortex and/or steroid 21-hydroxylase autoantibodies. In the course of natural history of autoimmune AD, the presence of adrenal cortex and/or steroid 21-hydroxylase autoantibodies identified patients at risk to develop AD. Different risks of progression to clinical AD were found in children and adults, and three stages of subclinical hypoadrenalism have been defined. Normal or atrophic adrenal glands have been demonstrated by imaging in patients with clinical or subclinical AD. Autoimmune AD presented in four forms: as APS type 1 (13% of the patients), APS type 2 (41%), APS type 4 (5%), and isolated AD (41%). There were differences in genetics, age at onset, prevalence of adrenal cortex/21-hydroxylase autoantibodies, and associated autoimmune diseases in these groups. "Incomplete" forms of APS have been identified demonstrating that APS are more prevalent than previously reported. A varied prevalence of hypergonadotropic hypogonadism in patients with AD and value of steroid-producing cells autoantibodies reactive with steroid 17alpha-hydroxylase or P450 side-chain cleavage enzyme as markers of this disease has been discussed. In addition, the prevalence, characteristic autoantigens, and autoantibodies of minor autoimmune diseases associated with AD have been described. Imaging of adrenal glands, genetic tests, and biochemical analysis have been shown to contribute to early and correct diagnosis of primary non-autoimmune AD in the cases of hypoadrenalism with undetectable adrenal autoantibodies. An original flow chart for the diagnosis of AD has been proposed.

Orthotopic liver transplantation for acute liver failure secondary to autoimmune hepatitis in a child with autoimmune polyglandular syndrome type 1

Autoimmune polyglandular syndrome type 1 (APS-1) is an autosomal-recessive condition characterized by hypoparathyroidism, autoimmune Addison's disease, and chronic mucocutaneous candidiasis. Autoimmune hepatitis develops in 10-20% of affected patients and has a variable course ranging from asymptomatic chronic liver disease to lethal fulminant hepatic failure. Liver transplantation has been documented previously in only two patients. We report a 14-yr-old boy with APS-1 who developed acute liver failure secondary to associated autoimmune hepatitis. He did not respond to corticosteroid therapy and was successfully treated with an orthotopic liver transplant.

The molecular basis of intractable diarrhoea of infancy

The intractable diarrhoeas of infancy present very major problems of clinical management. However, the conceptual importance of these conditions lies in the information that they may provide about normal small-intestinal function in humans: among such infants will be found the human equivalents of the 'knock-out' mice, in which targeted gene disruption allows sometimes unexpected insight into the regulation of intestinal function. The challenge posed by the intractable diarrhoeal syndromes, of working backwards from an apparently common phenotype to probably multiple genotypes, is, however, immense. Very few of these conditions have been described at the genetic level, although the molecular basis of pathogenesis has been better explored in recent years. The two major groups of intractable diarrhoea are due to (1) primary epithelial abnormalities (which usually present within the first few days of life) and (2) immunologically mediated (which generally present after the first few weeks). The high prevalence of autoimmune enteropathy among infantile autoimmune disease, in contrast to adult autoimmunity, is intriguing and may reflect constitutive abnormality of extrathymic lymphocyte maturation. The use of potent immunosuppressive drugs and increasing expertise with parenteral nutrition are improving the outlook of these previously fatal conditions. Viewed globally, however, the pressing problem is to treat effectively the millions of infants who die from severe persistent diarrhoea and wasting, which would certainly not be considered intractable in wealthy countries.